Portable radio transmission and reception equipment typically is configured for convenient carrying by operational personnel working remotely from a central communications control station. Generally, such remote use subjects the portable transmission-reception devices to a substantial amount of wear and environmental abuse. To enhance the portability and robustness of such devices, the necessary antenna mount now most popular is formed as a helical spring, the outer periphery of which is protected by a polymeric cover such as a "shrink wrap" sheath.
Because the small receiver-transmitters are serviced from time to time, and in view of the vulnerability of the small aerials to being otherwise contorted and abused during use, a convenient, removable form of connection serving both mechanical and electrical needs is employed for antenna attachment to the portable radio housings. Generally, an inexpensive and widely accepted "BNC" or bayonet type connector is employed to achieve this removability requirement. This connectors include a cylindrical base or shell portion which is rigidly coupled with the radio housing by a hex nut or the like and within which is mounted a dielectric surrounded tubular female connector. Forming part of the removable connector shell are two oppositely disposed bayonet pins or studs which extend outwardly from the shell surface a small distance.
Mounted upon the lower portion of the helical spring antenna is a dielectric surrounded male coaxial connector which, in turn, is surrounded by a rotatably mounted coupling section having a knurled hand graspable surface and an integrally formed outer body containing two oppositely disposed diagonal slots, each terminating in a circular shaped detent. An Annular spring member within the assemblage biases this body member toward the spring antenna thereto such that a spring generated release permits sufficient relative movement between the two principal coupling pieces to achieve a bayonet pin movement into the noted detent.
While the noted BNC type connector achieves a desirable "quick disconnect" feature, the spring biasing arrangement performing in conjunction with the noted ramp and detent approach permits a relative movement between the two connector pieces. This small amount of play or motion tends to permit a loosening of the connection over a period of use engendering unwanted interference or noise and the like detracting from transmission and reception by the devices. Additionally, the non-rigid form of coupling has been seen to promote a wear and failure of the connection at a pace for most applications which is considered excessive.
The same form of wear and distortion has been witnessed in closely analogous connectors for coupling one coaxial cable to another in electrical equipment. With such cables, two transmission paths are involved instead of one as is typical with antenna mounts. However, the same form of deficiencies tend to occur, spurious noise generating movement due to wear occurring over the lifespans of the equipment with which they are intended to be used.